Coastguard rescuers were called to the Newquay beach on Saturday, as the waves lapped at the edge of the stranded card.
Crews say the driver had gone onto the beach to turn around just before 2.30pm, but got stuck as the tide was coming in.
The man was put in touch with a local farmer, who arrived to tow the car free and just in time.
The elderly passengers, who were cold and suffering from medical conditions, were taken to a local hotel to warm up.
Posting on Facebook, Newquay Coastguard Rescue Team said: "Team paged to report of vehicle stuck in sand at Great Western Beach in Newquay
"The team’s role was to ensure no members of the public were at risk, not to assist recovery of the car.
"On arrival the team made sure everyone was safe and conveyed the drivers elderly passengers who were cold & had medical conditions to a local hotel where they were safe & warm.
"The driver had gone onto the beach in order to turn around but had got stuck in the soft sand.
"He was put in touch with a local farmer and arrangements were made to tow his car out.
"The farmer arrived in the nick of time as the tide was lapping at the wheels of the car.
"We remind people again, please do not drive onto beaches unless you are in a suitable vehicle & know it is safe.
"In any coastal emergency dial 999 and ask for the Coastguard".